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If this is sleep research’s golden age, then why are we all so tired?

We spend one third of our lives asleep, yet we don’t really understand very much about it. Not only are we terrible judges of how we’ve slept on any given night but we have few ideas on how to sleep better. We’re so desperate for better sleep that we’re turning to prescription medications at an astonishing pace.

The discovery of rem sleep led to the elaboration of a whole taxonomy of sleep. In Stage 1, the brain emits what are known as theta waves, which are slower and more regular than the waves emitted by a brain that’s awake; in Stage 3, it emits delta waves, which are even slower and have a much higher amplitude. (A person can be woken from Stage 1 sleep by a slight noise; by Stage 3, he might sleep through a loud crash.) Primates, marine mammals, birds, even fish have their own sleep patterns. Mouse lemurs, from Madagascar, snooze for more than fifteen hours a day, but only an hour of this is rem sleep. Bottlenose dolphins sleep with half their brains; this prevents them from drowning. Thrushes catch up on sleep by taking “catnaps” of less than thirty seconds apiece.

New technologies have made the study of sleep cheaper, easier, and less intrusive. In 2003, one expert in the field announced the “dawn of the golden age of sleep research.” Since then, hundreds, perhaps thousands, of academic papers have been written on topics ranging from “sleep problems among Chinese school-aged children” to the “sleep behavior of the wild black rhinoceros.” Currently, in the United States alone, more than two thousand sleep clinics are in operation. All of which raises the question: If this is sleep research’s golden age, then why are we all so tired?